Sensei is a CO enlisted in the Yellow Comet army.
Sensei is a former paratrooper rumored to have been quite the CO in his day. He possesses powerful infantry, superior firepower for Battle Helicopters, and increased movement range for transport units (Lander, APC, Transport Helicopter, and Black Boat), although his naval units have weaker attacks. He was also Kanbei's teacher, as was stated in Advance Wars 2: Black Hole Rising. During Advance Wars: Dual Strike he joins the allied nations in Omega Land along with another one of his students, Grimm.